Year % of total population 1960 38.7514853400392 1961 39.3865146941372 1962 40.0161777966371 1963 40.6319808821237 1964 41.2358021393775 1965 41.8341536352875 1966 42.4174696808706 1967 42.9935313847628 1968 43.559955788632 1969 44.1121408925971 1970 44.6058890147225 1971 45.0262416441081 1972 45.4236922911167 1973 45.8159831756046 1974 46.1958922828756 1975 46.5620539214701 1976 46.923909833645 1977 47.2790231104595 1978 47.6180115410084 1979 47.9682716392986 1980 48.1348493915819 1981 48.0432075321716 1982 47.8969609859797 1983 47.7588248633123 1984 47.639988513763 1985 47.5363946260277 1986 47.4376676970391 1987 47.3472082543241 1988 47.2726726230284 1989 47.225598302875 1990 47.2946486044712 1991 47.4942979557905 1992 47.7240820545773 1993 47.9500621817907 1994 48.1740765541825 1995 48.3990032912708 1996 48.6211176860785 1997 48.825892567874 1998 49.0205107542355 1999 49.2130433410145 2000 49.314555397408 2001 49.3078427973552 2002 49.2824320417315 2003 49.261560118738 2004 49.2427013975269 2005 49.2276348598188 2006 49.2157279489904 2007 49.2149329643184 2008 49.2190013659129 2009 49.2283388017985 2010 49.2489615233013 2011 49.2752748281004 2012 49.3058560507717 2013 49.3361428041232 2014 49.3664313042025 2015 49.4005167343343 2016 49.4339039834626 2017 49.4650249694554 2018 49.4978598276005 2019 49.5315020400418 2020 49.5854778379848 2021 49.641127282536 2022 49.6751545635544 2023 49.7016513252232